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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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The expenses and losses recorded for each transaction with the acquiree that was recognized separately from the acquisition of assets and assumptions of liabilities in the business combination.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The number of businesses acquired by the entity during the period.

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No definition available.

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Acquisitions (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended			1 Months Ended	2 Months Ended
	Dec. 31, 2014	Dec. 31, 2013 business	Dec. 31, 2012	Sep. 30, 2013	Dec. 31, 2012 business
Business Acquisition [Line Items]
Number of businesses acquired		1us-gaap_NumberOfBusinessesAcquired
Legal and consulting fees	$ (1,388)	$ 651	$ 700
Goodwill	236,044us-gaap_Goodwill	341,174us-gaap_Goodwill	359,863us-gaap_Goodwill		359,863us-gaap_Goodwill
SG&A
Business Acquisition [Line Items]
Legal and consulting fees	(1,594)	(34)	456
2013 Acquisitions
Business Acquisition [Line Items]
Fair value of purchase consideration		7,454		7,454
Payment for aggregate purchase consideration	328	1,864		2,322
Goodwill		2,466
2013 Acquisitions \| SG&A
Business Acquisition [Line Items]
Adjustment to payable, expense recorded	(1,611)	(236)
2013 Acquisitions \| Interest Expense
Business Acquisition [Line Items]
Adjustment to payable, expense recorded	75	36
2012 Acquisitions
Business Acquisition [Line Items]
Fair value of purchase consideration			43,263		43,263
Number of businesses acquired			4		3
Number of key markets			4
Goodwill			15,263		15,263
2012 Acquisitions \| Purchased Assets of Four Businesses
Business Acquisition [Line Items]
Fair value of purchase consideration		$ 146